S&P, the ratings agency, warned that a disorderly exit from the European Union could cost the UK around £130bn of economic growth in the next three years, cause a plunge of 10% in house prices and probably lead to a downgrade of UK government debt.

The agency also forecast rising corporate insolvencies, weaker banks, a 20% plunge in London’s office market,  and a jump in UK unemployment to levels last seen in the aftermath of 2008’s financial crash.